diff mbox

[v5,3/4] drm/i915: DSI pixel clock check

Message ID 1439897822-4004-4-git-send-email-mika.kahola@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Mika Kahola Aug. 18, 2015, 11:37 a.m. UTC
It is possible the we request to have a mode that has
higher pixel clock than our HW can support. This patch
checks if requested pixel clock is lower than the one
supported by the HW. The requested mode is discarded
if we cannot support the requested pixel clock.

This patch applies to DSI.

V2:
- removed computation for max pixel clock

V3:
- cleanup by removing unnecessary lines

V4:
- max_pixclk variable renamed as max_dotclk
- moved dot clock checking inside 'if (fixed_mode)'

V5:
- dot clock checked against fixed_mode clock

Signed-off-by: Mika Kahola <mika.kahola@intel.com>
---
 drivers/gpu/drm/i915/intel_dsi.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Ville Syrjälä Aug. 21, 2015, 10:57 a.m. UTC | #1
On Tue, Aug 18, 2015 at 02:37:01PM +0300, Mika Kahola wrote:
> It is possible the we request to have a mode that has
> higher pixel clock than our HW can support. This patch
> checks if requested pixel clock is lower than the one
> supported by the HW. The requested mode is discarded
> if we cannot support the requested pixel clock.
> 
> This patch applies to DSI.
> 
> V2:
> - removed computation for max pixel clock
> 
> V3:
> - cleanup by removing unnecessary lines
> 
> V4:
> - max_pixclk variable renamed as max_dotclk
> - moved dot clock checking inside 'if (fixed_mode)'
> 
> V5:
> - dot clock checked against fixed_mode clock
> 
> Signed-off-by: Mika Kahola <mika.kahola@intel.com>

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

> ---
>  drivers/gpu/drm/i915/intel_dsi.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
> index 4a601cf..781c267 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.c
> +++ b/drivers/gpu/drm/i915/intel_dsi.c
> @@ -654,6 +654,7 @@ intel_dsi_mode_valid(struct drm_connector *connector,
>  {
>  	struct intel_connector *intel_connector = to_intel_connector(connector);
>  	struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode;
> +	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
>  
>  	DRM_DEBUG_KMS("\n");
>  
> @@ -667,6 +668,8 @@ intel_dsi_mode_valid(struct drm_connector *connector,
>  			return MODE_PANEL;
>  		if (mode->vdisplay > fixed_mode->vdisplay)
>  			return MODE_PANEL;
> +		if (fixed_mode->clock > max_dotclk)
> +			return MODE_CLOCK_HIGH;
>  	}
>  
>  	return MODE_OK;
> -- 
> 1.9.1
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 4a601cf..781c267 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -654,6 +654,7 @@  intel_dsi_mode_valid(struct drm_connector *connector,
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode;
+	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
 
 	DRM_DEBUG_KMS("\n");
 
@@ -667,6 +668,8 @@  intel_dsi_mode_valid(struct drm_connector *connector,
 			return MODE_PANEL;
 		if (mode->vdisplay > fixed_mode->vdisplay)
 			return MODE_PANEL;
+		if (fixed_mode->clock > max_dotclk)
+			return MODE_CLOCK_HIGH;
 	}
 
 	return MODE_OK;